The girl's parents, James and Denise Closs, were found dead in the Barron home about 80 miles northeast of Minneapolis, but Jayme wasn't there.
On Wednesday, Barron County Sheriff Chris Fitzgerald confirmed that the teen's parents were killed by gunfire.
Investigators also believe Jayme was at home during the shooting based on details from the 911 call and evidence from the home.
At a news conference, police said they had received about 400 tips from the public since the 13-year-old disappeared and an Amber Alert was issued for her.
A girl resembling Jayme was spotted at a gas station in south Florida on Monday afternoon, according to a tip Miami police say they received. "I don't know that answer", the sheriff said during the news conference. No vehicles were found in the immediate area, the sheriff said.
He implored the public to share any suspicions, including any behavioral changes in people they know, no matter how small.
He didn't say how the couple died, but the Federal Bureau of Investigation office in Milwaukee said the teen was likely abducted from her home early Monday morning by an unknown person with a gun.
Jayme's grandfather, Robert Naiberg, told The Associated Press on Tuesday that nothing seemed amiss at a Sunday gathering, which was to celebrate the birthday of a grandson who is cousins with Jayme.
Fitzgerald said additional agencies, including the Federal Bureau of Investigation, are involved. Some attendees shared heartwarming stories about the family and vowed to wear their blue ribbons until Jayme is home.
Both James and Denise Closs were long-time employees of the Jennie-O Turkey Store in Barron, Jennie-O's parent company Hormel said.
Fitzgerald said there are 200 law enforcement on ground.
The sheriff has said previously that authorities consider Jayme to be an endangered missing person and not a suspect, and he's indicated that finding Jayme is his goal. "We pray for her safe return".
Authorities have described Jayme as a 5-foot-tall, 100-pound 13-year-old girl with strawberry-blonde hair and green eyes.
The FBI, state investigators and the National Center for Missing and Exploited Children are assisting Barron County in the search for the girl that Fitzgerald described as a "sweet and shy 13-year-old who enjoys dancing and sports".
Anyone with information about the case is asked to call the tipline - 855-744-3879.
Even while Officer Stetzer is not exactly sure how he will be assisting the school district yet, he said he is well aware of the healing power of dogs and especially the department's therapy dog, Badge.